correlational
Taking 3 grams of glycine before bed doesn't seem to change the overall structure of sleep stages in people who have trouble sleeping
Scientific Claim
Glycine ingestion (3 g) before bedtime is associated with unchanged sleep architecture in individuals with chronic sleep dissatisfaction, as measured by polysomnography
Original Statement
“Glycine improved subjective sleep quality and sleep efficacy (sleep time/in-bed time), and shortened PSG latency both to sleep onset and to slow wave sleep without changes in the sleep architecture.”
Evidence Quality Assessment
Claim Status
overstated
Study Design Support
Design supports claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The study uses 'without changes' which implies causation, but the design is a non-randomized cohort study with unclear blinding and control group status. Only association can be claimed.
Evidence from Studies
No evidence studies found yet.